The family
Clariidae includes about a hundred different species. All are scaleless fish
with four pair of barbles. They are able to breathe air by means of a labyrenthic
organ arising from the gill arches. Some of the fish “walk” from
one water body to another during wet seasons using their pectoral fins. Others
species burrow. The family includes the following genus: channallabes, clariallabes,
clarias, dinotopterus, dolichallabes, gymnallabes, heterobranchus, horaglanis,
and vegitglanis. Most of the walking catfish are in the genus clarias.

Clarias batrachus
have become well established in Florida, and have been found in Nevada. They
have a strong potential to be a pest due to their ability to migrate across
land, and the fact that they devour almost anything in sight. They first
came into the U.S. for sale in the aquarium-fish trade in the mid 1960's.
They have a tolerance to a wide range of temperatures, and have been found
in intracoastal waterways with salinities of 18ppt.